1. Field of the Invention
This invention relates to condensate pans and liquid-level-activated float switches, specifically to a fluid-collecting tray or pan with an integrated support system configured to provide it with enhanced material strength and improved safety during its use, particularly when the pan is used to support of a heavy fluid-producing unit while suspended via lumber, struts, and/or other laterally-extending under-pan supports and cable from an overhead location. The structured design and materials used for manufacture of the present invention pan allows it to resist cracking and premature failure during installation, as well as failure during its use in various fluid collection and overflow prevention applications. When mentioned hereinafter, the terms “tray” and “pan” are to be considered interchangeable, unless specifically noted otherwise. The primary use contemplated for the present invention pan is support and overflow prevention for a fluid-producing unit, wherein if the usual discharge pathway for produced fluid becomes blocked and causes fluid to accumulate in the pan and rise above a pre-determined level considered safe, a float switch associated with the pan will deploy and promptly shut-off the unit's operation to prevent damage to the unit and/or its surroundings. An equally important use of the present invention pan is management of the routine cycles of fluid accumulation and evaporation expected during the support of a system or unit that at least periodically produces condensate as a by-product of its operation, perhaps as a result of inadequate insulation. Spaced-apart uppercuts incorporated throughout the inside bottom surface of the pan collectively provide balanced weight distribution of accumulated fluid, since the uppercuts each have the capability of isolating a small amount of fluid separately from that collected in other parts of the pan, instead of allowing accumulated fluid to run together and pool in a single area of the pan, which could lead to bowing and/or buckling in that area and a potential for pan collapse, particularly if the pan is supporting a heavy object in an elevated position, such as support of the air handler of an air conditioning system in an out-of-the-way position near the ceiling of a garage. Further, by capturing routinely accumulating fluid in this manner, excess fluid is not directed to the float switch to cause premature unit shut-off or pooling of fluid around the float body that could transport debris to the float body, and/or promote algae growth on it, both of which could seriously interfere with proper, reliable, and repeat float body deployment when needed for emergency shut off of the fluid-producing unit to prevent overflow or damage.
In many common applications, such as the elevated support of an air handler in a portion of a residential building, such as a garage, the integrated support system of the present invention pan will typically include three supports each having a non-linear perimeter configuration that is shaped to reduce the number of pressure points that could lead to cracking of the pan material during installation and extended periods of use. Thus, in ensuing discussions herein, reference will often be made to a center support and two non-linear supports, which relate back to this most preferred embodiment of the present invention contemplated for residential use. However, more than three longitudinally-extending supports are contemplated for other applications as long as each support used had a non-linear or arcuate perimeter that reduces the formation of pressure points and is otherwise configured and positioned between the perimeter grommets to provide sturdy and balanced support of a fluid-producing unit with minimal stress line presence at the interface of the supports and the bottom surface of the pan. The non-linear perimeter of the present invention center support and its widened convex lower central portion, in combination with the two lateral supports typically positioned on opposite sides of the center support that also have non-linear perimeters and a non-linear longitudinal axis, allow the weight of a heavy fluid-producing unit positioned on the supports to be distributed across a large portion of the pan's bottom surface, thereby reducing the presence of stress lines that could lead to premature cracking of pan material and its failure. Also, the high-friction damper inserts associated with the top surface of each of the three supports collectively provide an important safety-enhancing structural feature of the present invention pan by reducing the potential for sliding movement of the supported fluid-producing unit relative to the pan that could otherwise create a weight imbalance, float switch malfunction, and/or enhanced likelihood of pan collapse. Typically, one damper insert is secured into each recess on the top surfaces of the center support and lateral non-linear supports. However, several damper inserts in a vertically stacked array may also be used to adjust the fluid-producing unit to an optimum working height. In addition to maintaining the fluid-producing system in its intended position of use upon the present invention pan, thereby avoiding unexpected weight transfer that could lead to pan collapse, the damper inserts may also be relied upon to reduce vibration and provide enhanced heat deflection around the supported fluid-producing unit.
Further, integrated pan structure also includes the previously mentioned uppercuts that provide balanced fluid capture within the inside bottom surface of the pan and one stress-transferring member located between adjacent non-linear supports, wherein the transfer of stress between the longitudinally-extending supports reduces the likelihood of the pan warping and buckling under load. It is preferred for only one stress-transferring member to be positioned on each side of the center support so as not to entrap large quantities of fluid centrally within the pan to avoid bowing and distortion, with the stress-transferring members also providing the benefit of lowered manufacturing cost since they allow thinner pan materials to be used without a reduction in weight load capability. In addition, the staggered interior-projecting edges of perimeter grommets and angled corners, in combination with the primarily polycarbonate material used for construction of the present invention pan, significantly help to reduce stress points and the potential for pan cracking as a result of handling during installation, a common problem experienced with prior art pans. Another important safety-related structural feature of the present invention is the presence of multiple laterally-extending undercuts incorporated into the outside bottom surface of the present invention pan. They are each configured to receive a 2″×4″ piece of lumber, strut, or other under-pan support contemplated for use under the bottom surface of the present invention pan to support it in an elevated and suspended position via cable connected to an overhead location, with the installer selecting the number and positioning of undercuts best used for balanced support of the pan in each application. With the under-pan supports each laterally isolated and fixed in position via the undercuts, weight shifts due to fluid accumulation in the pan, vibration, and/or other factors cannot easily cause the under-pan supports to slip sideways relative to the pan whereby the pan and the heavy fluid-producing unit it supports could eventually become unbalanced and placed at risk for falling, where an automobile or people moving around a motor vehicle under the pan could become injured. Additionally, present invention pan structure also includes a quick-mounting shelf area for rapid attachment of a drain line connection having a complementary configuration and a fluid-level-activated float switch in fixed association therewith. Attachment of the drain line connection to the shelf automatically places the float switch in a leveled orientation relative to the pan. Thus, when the pan is prepared for support of a fluid-producing unit and placed into a level orientation during its installation, the deployable float body within the float switch attached to the pan instantly and without other adjustment becomes poised for proper, reliable, and repeat deployment to shut off the fluid-producing unit supported by the pan when excess fluid from the unit collects in the pan beyond a pre-determined threshold amount considered safe. The shelf contains a drain line opening and is also positioned adjacent to a recessed area formed from multiple horizontally-extending and vertically-stacked arcuate ribs that are configured to protect the float switch housing against side impact during installation and use. To support a heavy fluid-producing unit, the present invention requires rugged construction and the use of materials that are strong, impact resistant, impervious to corrosion, unaffected by extreme ambient temperature fluctuations, and resistant to buckling, bowing, warping, distortion, and collapse during extended use. Further, depending upon the intended application, it may also be preferred for the present invention pan to have UV-resistant capability. In addition, although not critical, it is preferred for at least some of the strengthening features of the present invention to have a nesting configuration for efficient stacking one upon the other for compact storage and transport.
2. Description of the Related Art
When air conditioning condensate and other condensates are collected, there is often a risk of overflow or back-up into the system producing it. As a result, liquid-level float switches have been employed with collection pans to shut-off the source of condensate flow when the amount of fluid collected in them exceeds a predetermined depth considered safe. The goal of the present invention is provide a tray or pan for the collection of condensates and other fluids wherein the pan is made from rugged materials and has a sturdy construction that facilitates installation, shortens installation time, provides stable installation, reduces the potential for cracking during installation particularly during elevated installations, reduces the possibility of pan collapse due to unbalanced weight distribution when fluid accumulated in the pan, minimizes maintenance after pan installation, and takes the guess-work out of selecting and mounting a float switch to provide immediate, reliable, and repeat electrical shut-off deployment of a fluid-level-activated float body when fluid accumulating in the pan exceeds a pre-established or custom-set threshold amount. Further, since air conditioning condensate collection pans are typically installed in hot attics, garages, and other places where temperatures can easily exceed 150 degrees Fahrenheit and where significant temperature fluctuations can also occur, and further since many prior art plastic condensate collection pans have insufficient construction whereby a float switch mounted on its upper edge will lean in over a period of time and no longer be maintained in the needed vertical orientation for a prompt and reliable response to excessive condensate collection in its associated pan, the present invention is also configured to overcome the lean in problem through integrated structural features that include perimeter grommets, a quick-mounting shelf area, and multiple horizontally-extending arcuate ridges in vertically-stacked array that are adjacent to the shelf area for float switch housing protection. In addition, the float switch assembly contemplated for use with the present invention pan is in fixed attachment to a drain line connection having a configuration complementary to that the pan's quick-mounting shelf area, which significantly reduces installation time and assures automatic leveling of the float body relative to the pan, so that when leveling of the pan occurs, the float switch is also leveled and remains in its original location and leveled orientation during the entire time period of use, and will not be subject to changes in orientation over time. Also, since the float body used with the present invention is not routinely in contact with accumulated fluid as a result of the segregated and balanced fluid collection provided by its spaced-apart uppercuts, there is a reduced likelihood of fluid pooling around the float body and it is less likely to become clogged with mold, algae, and/or debris, which could otherwise cause it to malfunction, resulting in continued and reliable float body operation during the entire time period anticipated for use. Another problem overcome by the present invention pan is the likelihood of pan failure resulting from cracking, bowing, distortion, bending, warping, buckling, and/or collapse due to fluid distribution imbalance, particularly when the pan is suspended in an elevated position. Extended stress lines are also avoided by many features integrated into the present invention pan, including the use of curved perimeter surfaces in the non-linear support members, the widened convex lower central portion of the center support, the staggered interior-projecting edges of the grommets, the angled corners, the corrugated configuration of uppercuts and undercuts, the undercuts being configured for secure and fixed receipt of under-pan supports, the perpendicular interfacing of the longitudinally-extending support members with the horizontally-extending uppercuts and undercuts, and the stress-transferring members between the non-linear support members. No other apparatus is known that functions in the same manner or provides all of the advantages of the present invention.